?? ?? ??? ??? ?? ??? ? ???? ???? ??? ?? ???? ???? ??? ? ??????????????? ??? ?? ???? ???? ????????? (?????)?? ???? ?? ???????? ???? ??????, ????????????, ???? ???? (???????? ??)If a grammatical principle that is definitely extra to ????is a vowel ??and there is no other alternative besides a vowel ??then that grammatical principle can